Spark plug provided with an ionizing catalytic element



Nov. 26, 1935. c, MICHEL 2,022,140

SPARK PLUG PROVIDED WITH AN IONIZING CATALYTIC ELEMENT Filed April l0, 1935 FIGA Guai-ing of end mel, 2? mpi-egmfed wHL hui arm A brom d@ UNITED STATES PATENT OFFICE SPARK PLUG raovmEn wlrn AN romzING cA'rALrrrc ELEMENT Charles Michel, Paris, France Application April 10, 1935, Serial No. 15,707 In France September 29, 1934 3 Claims. (Cl. 12S-169) 'I'he object of the present invention is improvehas further proved that by employing an ionizing ments to ignition plugs, such as employed in inmixture containing .002 milligram of radium ternal combustion engines, provided with a radiobromide and 2 milligrams of barium sulphate for active substance with a view to ionizing the mass each spark plug in an internal combustion engine 5 of explosive gases thus considerably increasing the there was a resulting economy of 14% oi' gasoline 5 eiliciency of the engine. While, with .005 milligram of radium bromide and Said improvements consist: 5 milligrams of barium sulphate, the economy in 1. In the titration of the constituent parts of gasoline obtained, in the same engine, rose to 20%. the radio-active mixture (for instance radium For proportions very much lower than these bromide and barium sulphate) employed respecvalues only a reduction of the explosive potential 1o tively in the proportion of 1 to 1000, the quantity of the electrodes is obtained whereas, with greater of radium salts not exceeding ve micrograms. proportions, the gassy medium becomes such a 2. In the incorporation of said mixture into a high conductor of electricity that leakage circuits porous enamel possessed of a high melting point, are set up along the walls of the insulator, said cirsaid enamel not being Hable to deterioration under cuits being liable to interrupt the jumping of the 15 the action of intense heat or contact with gases. spark across the gap of the electrodes.

3. In the application of said enamel, preferably 'I'he invention also provides for the addition to on to the body of. the sparking plug in order adethe means above described of. any other secondary quately to ionize the gassy mass, and means capable of intensifying the phenomenon 2o 4. In the magnetizing of the center electrode of of ionization and, in particular, means consisting zo the spark plug. in magnetizing the center electrode of the spark Attempts have already been made to incorplug. porate radium, or a similar substance, in the in- The annexed drawing shows as an example a v sulating sleeve of the spark plug, by covering said sparking plug embodying the features of invention 26 sleeve with insulating varnish. hereinabove described. A 25 Now, experience has proved that said insulat- Fig. 1 shows an elevation with parts broken ing varnish had the ellect of preventing the ionizaway, o'f said sparking plug. ing emanations and that, in order to overcome this Fig. 2 is a bottom view of the same plug. disadvantage, it was necessary to have recourse to Fig. 3 is a fragmentary View, partly in section 30 massive amounts of radio-active substance, whichA and partly in elevation, through the bottom part 430 is liable to increase the cost price of an ionizing of the plug of Figs. 1 and 2; while spark plug considerably. Indeed, a spark plug Fig. 4 is a view similar to Fig. 3.4)! a modified made of radio-active substance under such conconstruction. ditions would cost several hundred francs. Referring to the drawing, I is the body of the a5 In order to cope with these disadvantages, the plug, the body being grounded, and 2 is the cen- 85 process which forms the subject matter of the intral electrode of said plug. As shown in the vention consists in incorporating a suitably ti drawing, the bottom of the plug iscovered with a trated radio-active mixture into an enamel poslayer 3 of radio-active mixture incorporated into sessed of a high fusion point, suitably porous and an enamel having a high fusion point suitably po- 40 sulciently heat-proof. According to the invenrous and sufciently heat proof by which the cen- '40 tion, an enamel of this description is applied, not tral plug is surrounded by said substance and the to the center electrode, the area of which-would be ionization is produced in the best of conditions. too small, but to the shell or earthed electrode, the In Fig. 4 the second electrode extends inwardly area of which is much greater. In this manner through the wall of the plug, rather than being ionization is not limited to the sparking zone or constituted by the wall itself. 46 gap between the two electrodes but extends It is to be understood that the invention is not throughout the gassy mass contained within the limited tothe features disclosed in this specificaexplosion chamber. As to the ionizing member tion and annexed drawing but may be variously itself, it is constituted, according to the invention, modified within the scope of appended claims.

by a mixture, in suitable proportions, of. a radiowhat I claim is; 60

active salt such as radium bromide and barium 1. A spark plug comprising a central electrode 4 sulphate. Experience has proved to the applicant and a grounded body the bottom of which surthat the respective proportions of said salts Should rounds the bottom end of said central electrode preferably be aS 1 t0 1.000 in Order to Obtain the and is covered with a layer of radio-active subdesired eect t0 a maximum degree Expel'len stance comprising an ionizing, catalytic radio-ac- 55 2 2,022,140 tive mixture incorporated into porous enamel hav- 3. A spark plug according to claim 1 in which ing ahigh melting point. the radio-active mixture comprises radium bro- 2. A spark plug according to claim 1 in. which mide and barium sulphate in the proportion o1 the radio active mixture comprises radium broone part of the former to one thousand of the 6 mide and barium sulphate in the proportion of latter. the amount of radium bromide not exceed- 5 one part of the former to one thousand parts of ing ve micrograms. thelatter. CHARLES MICHEL. 

